Smoking of tobacco, particularly in the form of cigarettes is a widespread practice which, while providing pleasure and satisfaction to the smoker, presents a substantial hazard in the form of fire. While the fire hazard is not a significant problem when smokers exercise a proper degree of care in the smoking of cigarettes and disposal of the ash and resulting residue, however, experience has shown that substantial carelessness is found among smokers. Consequently, efforts have been made in particular to improve fire safety with respect to smoking of cigarettes, although attempts have also been made to improve safety with respect to cigar and pipe smoking. The area of safety with which this invention is primarily concerned is safety relative to smoking of cigarettes, although the invention is not deemed limited to that specific type of tobacco material.
Predominant causes of fires as a consequence of smoking cigarettes are the careless and inadvertent dropping of burning cigarettes onto or into combustible materials and improper disposal of ashes and the butts which are not fully extinguished at the time of disposal. Burning cigarettes frequently fall from ashtrays where they are temporarily placed during the course of the smoking and drop onto furniture and carpets. Even if the cigarettes that drop do not result in igniting the materials or objects upon which they land, they invariably at least cause damage to the article such as by scorching, thereby producing burn marks. Fires are also frequently caused by careless tossing of a burning cigarette into an improper container such as a trash can containing highly combustible material such as paper or other similar types of materials. Another major cause of a substantial number of fires as a consequence of careless smoking habits is the smoking by persons who inadvertently fall asleep while lying or sitting up in bed as well as sitting in a chair. Invariably, the cigarette falls from the person's hand and drops onto floor carpeting or the upholstered material of a chair or the highly combustible bed clothes in the case of those who smoke in bed.
Prior efforts to eliminate the fire hazard associated with smoking of cigarettes have primarily centered on providing of a container-type shield into which a cigarette is placed during the course of smoking. One example of such a device is illustrated in U.S. Pat. No. 2,454,631 issued to Z. Chneerson on Nov. 23, 1948. That patent illustrates a typical device which comprises an elongated tubular container which contains the cigarette and is provided with a mouthpiece to enable smoking. The cigarette is physically restrained and supported in a coaxial position within the elongated container and has the one end coupled with the mouthpiece. A number of apertures are formed in the wall of the container to permit airflow necessary to effect combustion. Another example of a container type of device is that disclosed in U.S. Pat. No. 2,625,163 granted to R. F. Jones on Jan. 13, 1953. The Jones structure again includes an elongated container provided with a mouthpiece at one end. The container, as in the case of the Chneerson unit is provided with elements to support the cigarette in fixed, coaxally spaced relationship to the walls of the elongated container and to hold the cigarette at one end in association with the mouthpiece to enable smoking. Again, apertures are formed in the container wall to permit airflow for purposes of enabling combustion. While Chneerson provides a number of apertures distributed throughout the entire length of the chamber containing the cigarette, Jones provides apertures only at each of the extreme ends of the container. Also, while Chneerson provides a number of spring fingers on the interior of the chamber to provide support for the cigarette and to also function in knocking off the ash as it accumulates during the course of burning, Jones provides a number of small lugs that extend from the interior of the chamber into supporting contact with the cigarette. Each of these two examples characterized also by a relatively large physical structure. As a consequence, the safety devices as exemplified by either of Chneerson's or Jones' structures are cumbersome to utilize as well as being relatively expensive to fabricate. Such devices have not been accepted by smokers, and thus, there remains a need for a safety smoking device to perform the desired safety functions.
More recent efforts in providing safety devices for cigarettes are exemplified in U.S. Pat. No. 4,289,149 issued to Kyriakou on Sept. 15, 1981 and U.S. Pat. No. 3,886,954 issued to Hannema on June 3, 1975. Each of these two patents disclose structures which are substantially smaller in physical size as compared to the Jones and Chneerson type structures. Each of the Kyriakou and Hannema patents utilizes a double-walled tubular shield structure with the two walls coaxially disposed to each other, thus forming an annular chamber to provide protection against direct contact with the cigarette and to reduce the likelihood of heat being transferred from the cigarette through the device to any material or structure on which the cigarette and its container may be placed. Kyriakou provides a container having a number of apertures formed throughout the extent of the container walls to permit airflow with respect to the cigarette. For support of the cigarette, Kyriakou only provides a single ring which engages with the cigarette approximately at its midpoint with the ring being carried by the inner cylindrical wall.
Hannema, while having a double walled structure, differs from Kyriakou in that it does not include the conventional type of mouthpiece as the double-walled tube is formed such that one end of the tube functions as a mouthpiece. Hannema provides a structure which is self-contained to permit smoking and is deemed to be a disposable throwaway type of unit as contrasted to the more general type of device which is designed to enable replacement of cigarettes within the chamber itself with the device thus being reusable. The double-walled tubular structure of Hannema is provided with end caps at each end and provided with apertures to permit airflow to the cigarette through one end cap and from the cigarette through the cap at the other end functioning as a mouthpiece. Additionally, apertures and passageways are provided in the double walled structure to permit airflow through the cylindrical wall with respect to the cigarette. The outer wall is provided with apertures permitting airflow relative to the annular chamber and the inner wall carries a number of projections which provide support for maintaining the cigarette in coaxally spaced relationship to the inner wall with each of those projections also being formed with a passageway to permit the airflow relative to the annular chamber between the two walls and the cigarette itself. These passageways are blocked by the cigarette until such time as the cigarette has burned and produced an ash which will not necessarily obstruct the airflow to those passageways. However, smoke will also intermix with air in the annular chamber as it cannot readily escape, thereby resulting in a reduced oxygen content with consequently inhibited combustion of the tabacco, thus producing a greater quantity of the undesirable combustion products deemed a health hazard. While these structures of Kyriakou and Hannema provide a degree of protection against inadvertent igniting of combustible materials upon which they may be placed, the devices have not been employed. One of the apparent reasons such devices have not been employed is that the double-walled structure is difficult to form and represents a substantial expense and significantly inhibits airflow, thereby resulting in relatively poor combustion of the tobacco with a consequent increase in production of the undesirable solid combustion products.